A conventional industrial robot has been operated in a state in which it is separated from people by being enclosed with a safety fence. When teaching is performed, an operator holding a portable operating panel performs teaching work on the inside of the safety fence, and, when automatic start-up is performed, after people are evacuated from the inside of the safety fence, the taught program is run (see PTL 1).
Meanwhile, robot systems that can coexist with people without safety fences by using a function for monitoring the presence of an object within the operating area of a robot (monitoring function) are becoming widespread. For example, a technique in which an external force applied to a robot is detected with a force sensor or a contact sensor, and the robot is stopped when the external force increases, and a technique in which the distance between a person and a robot is monitored with an area sensor, and the robot is stopped when the person approaches the robot are known.